Rupert von Thal and his companion, Mrs. Beatrice Mapp, are travelling through a jungle before they're set upon by a gigantic scorpion like creature.
The Fifth Doctor and Nyssa are stuck in a distant prehistoric Earth that should never have been, but there he has to confront the Scorpion King and in him, His Greatest Failure.
Tropes:
- Alternate Timeline: A prehistoric Earth that should never have existed.
- Antagonist Title: The Boy That Time Forgot.
- Big Creepy-Crawlies: The giant scorpion creatures and spiders.
- Call-Back:
- The scorpions have names given to them by the Scorpion King. One is Kranlee which might be a reference to Lord Cranleigh and the other one is called Teegarana which means "Mouth on Legs" in the Scorpion King's "native language".
- The Doctor not being good with heights gets a mention.
- Tegan having been dropped off at Heathrow gets mentioned.
- The Doctor says that time is Circular.
- Adric is fond of spiders, mentioning that his people have a particular affinity with them.
- The Cameo: Thomas shows up for a short scene at the end.
- Continuity Nod:
- Thomas Brewster stealing the TARDIS is part to the start of the plot.
- The ship crashing into the Earth killing the dinosaurs.
- The Doctor mentions Iris Wildthyme to Nyssa, whom she is aware of after once spending Christmas with her, Tegan, Adric and the Doctor.
- Clarke's Third Law: The mathematical equation that warps reality.
- Cold Open: With Rupert and Mrs. Mapp fighting a gigantic 12 (or is it 14!?) foot scorpion.
- Dropped a Bridge on Him: The elderly Adric casually mentions that all the sleeping Cybermen on Briggs' freighter were eaten by the scorpion people a long time ago.
- Fed to the Beast: The Scorpion King very unceremoniously shoves the Doctor into a pit with a gigantic insectoid.
- Go Mad from the Isolation: Hundreds of years with only scorpion people to talk to has not exactly done wonders for the Scorpion King's sanity. He genuinely believes that tossing the Doctor into a pit with his pet monster is "a bit of fun" and his desperate attempts to get Nyssa to be his bride are decidedly unhinged.
- Heroic Sacrifice: Rupert shoves the last two Grandparents off of Star so that the others will be able to return to Victorian London.
- Idiot Ball: Yes, Scorpion King, explain to your last two loyal followers that your departure from their world might not only mean they could revert to a feral state, but even worse still their entire timeline to stop existing.
- Improvised Weapon: Rupert makes a flail out of spider-silk and a bunch of heavy rocks, and keeps a group of Grandparents at bay.
- I Take Offense to That Last One: The Grandparents are hurling insults at Rupert during the Improvised Weapon scene, like "Pest!" "Mammal!" and "Fat!" the last one has him going "Oi!"
- The Man Behind the Monsters: The Scorpion King is an old man with a Psychic Link commanding an army of arachnids (Scorpions and spiders alike).
- Mythology Gag: Iris Wildthyme is mentioned as being around in Victorian London, but the Doctor really doesn't want to meet up with her under any circumstances.
- Not Named in Opening Credits: Well he is, named the Scorpion King. But not by his real name.
- Older Than They Look: The Doctor mentions that despite the Scorpion King looking older, he is the senior by many centuries. Though the Scorpion King himself is over 500 years old as well.
- Organic Technology: A Spooky Séance masquerades and functions as a supercomputer that ends up shunting the Doctor and several people into the past.
- Precursors: The Grandparents which are kept in a crashed ship which are outside of the regular psychic web.
- Psychic Link: Between the Scorpion King and a telepathic lens.
- Redemption Equals Death: Adric makes up for his misdeeds by performing one last Block Transfer Computation, getting the TARDIS back to the Doctor and exhausting his life force in the process.
- The Reveal: The Scorpion King/The Boy That Time Forgot is Adric.
- Sequel Episode: The Doctor and Nyssa are still without the TARDIS, thanks to Thomas Brewster. As well as one to Earthshock.
- Shout-Out: The TARDIS is said to have a Flux Capacitor.
- Shut Up, Hannibal!: Though the Hannibal side had weakened by a bit, the Doctor tells the Scorpion King to stuff it.
- Starfish Language: A side effect of the TARDIS not being around and hence, no Translator Microbes.
- Timey-Wimey Ball: The Doctor having the seance went back in time, changed the course of the freighter, which saved the Scorpion King's life, which had him draw in the Doctor from the future where the Doctor was reciting the equation in the seance.
- Turned Against Their Masters: The arachnids when they begin to theorize that their master the Scorpion King might breed with Nyssa, and their children would eradicate them.
- What Happened to the Mouse?: If Adric used Block Transfer Computation to transport both himself and Briggs' freighter into the bubble universe, then what was the "asteroid" that crashed to earth and killed the dinosaurs?
